1. Field of the Invention
The present invention relates, in general, to trimaran type wing-in-ground effect ships and, more particularly, to a trimaran type wing-in-ground effect ship, which consists of one main hull and two half-submerged sub-hulls each having a minimum waterplane area capable of minimizing the wave resistance and appendage resistance of the ship, thus reducing resistance-induced speed loss on rough water, and which also has wings and an effective propelling mechanism, designed such that they produce a strong lift force allowing an effective take-off of the ship running on water even at a low speed, and which is thus excellent in its seakeeping and maneuverability on rough water.
2. Description of the Prior Art
Wing-in-ground effect ships (herein below referred to simply as xe2x80x9cWIG shipsxe2x80x9d) are vessels that sail on water at high speeds and take off from the water to fly in the air over the water. Such a WIG ship is designed such that it produces a surface effect by air captured under the main wings when it sails on water at a high speed with the wings suspended over the surface of water at a height of about 2xcx9c3 meters. Due to such a surface effect, the WIG ship increases the lift force without inducing an increase in the drag force, and so the WIG ship runs on water more stably and safely in comparison with conventional vessels or airplanes, thus having been used as a superhigh-speed water transportation system with excellent water transportation efficiency. Such WIG ships typically use a PAR (Power Augmented Ram) mechanism or an air cushion mechanism, and are typically used as vessels sailing on inland seas or inland waters, such as rivers or lakes without waves, in place of sailing on open seas along regular service lanes.
Examples of conventional vessels using such air cushion mechanisms are air cushion vehicles (ACV, so-called xe2x80x9chovercraftsxe2x80x9d) and surface effect ships (SES). In such an ACV or SES, two or more downward thrusting fans are installed under the skirt provided at the lower portion of the hull, and downwardly thrust highly pressurized air so as to pneumatically lift the hull over the surface of water. The ACV or SES can somewhat effectively run on quite water at a superhigh speed.
However, such an ACV or SES is excessively increased in the wave resistance and appendage resistance while sailing on rough water, and so it is almost impossible for them to accomplish desired take-off speeds or to produce a desired lift force required to take off from the water. Therefore, the ACV or SES cannot take off from the water when they sail on rough water. Another problem of such an ACV or SES resides in that they are inferior in seakeeping, and so they cannot stably take off from or alight on water. Therefore, the ACV and SES are in the early stages of being used practically even though they have superhigh-speed sailing effect and excellent water transportation efficiency. In an effort to accomplish the superhigh-speed sailing effect of vessels, large-scale thrusting engines or machines capable of generating high propelling force may be used in some vessels. However, the use of such large-scale thrusting engines or machines in vessels results in an exorbitant increase in the price of vessels, excessive consumption of fuel, and an increase in the plying cost, thus degrading economic efficiency of the vessels.
Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a trimaran type WIG ship, which consists of one main hull and two half-submerged sub-hulls each having a minimum waterplane area capable of minimizing the wave resistance and appendage resistance of the ship, thus reducing resistance-induced speed loss on rough water, and which also has wings and an effective propelling mechanism, designed such that they produce a strong lift force allowing an effective take-off of the ship running on water even at a low speed, and which is thus excellent in its seakeeping and maneuverability on rough water.
In order to accomplish the above objects, the present invention provides a WIG ship comprising a main hull, two sub-hulls, two main wings, two outer wings, two sailing propellers, a flight propeller, a rudder, and a horizontal stabilizer, wherein the main hull is intermediately positioned between the main wings and comprises a slender and half-submerged body, and bears 60% of the total displacement of the ship; the sub-hulls are respectively provided under the outer ends of the main wings, and each bear 20% of the total displacement, and act as end plates; the sailing propellers each supply 25% of maximum required power of the ship; and the flight propeller supplies 50% of the maximum required power.